Marielle buys an equal number of $50$¢ and $75$¢ candy bars and spends $\$10$, not including tax. How many candy bars did she buy altogether?
Let $x$ be the number of candy bars she bought for each type. Thus, \[(\$0.50)x+(\$0.75)x=\$10.00\] Combining the like terms on the left side, we see that \[(\$1.25)x=\$10.00\] Dividing, we see that $x=8$. She bought $8$ of each candy bar, so she purchased $\boxed{16}$ candy bars in total.